Three days after reporting their 3rd H5N1 case of 2024 - a fatal infection in a 9-y.o. boy from Kratié Province - Cambodia's MOH has posted a statement (see below) regarding the apparent mild infection of his 16-y.o. brother.
Details are scant, but it seems likely this case was detected via routine testing of close contacts. The patient was described as having `no respiratory symptoms', but it isn't clear whether any other clinical signs (e.g. fever, diarrhea, etc.) were present.
H5N1 infection severity runs the gamut from severe or fatal to mild/asymptomatic. It's infamous 50% fatality rate is probably overstated, since mild or moderate cases are less likely to seek medical care, making it unlikely they will be tested, or reported.
Over the past 12 months Cambodia has reported 10 cases, of which 5 were fatal, 2 were moderately severe, and 3 were described as `mild'.
Kingdom of Cambodia, Nation, Religion, King
Ministry of Health
Cases of bird flu in 16-year-old boy
The Ministry of Health of the Kingdom of Cambodia would like to inform the public that there is another case of bird flu in a 16-year-old boy and was confirmed positive for H5N1 bird flu virus (H5N1) from the National Institute. Public Health on February 11, 2024, living in Kapo 1 Village, Sangkat Or Russey, Kratie City, Kratie Province. The boy had no respiratory symptoms and was the brother of the boy who died on February 8, 2024.
The National and Sub-National Emergency Response Team of the Ministry of Health has been cooperating with the working groups of the Ministry of Agriculture, Forestry and Fisheries and the Ministry of Environment, local authorities at all levels to actively investigate the outbreak of bird flu and respond. In accordance with the methods and technical protocols, continue to search for sources of transmission in both animals and humans, and continue to search for suspected and affected cases to prevent transmission to others in the community, and distribute Tamiflu to close contacts. And conduct health education campaigns for the people in the above-mentioned villages.
The Ministry of Health would like to remind all citizens to be careful about bird flu because H5N1 bird flu continues to threaten the health of our people and also would like to inform you if there are symptoms. Fever, cough, runny nose or shortness of breath and a history of contact with sick or dead chickens during the 14 days before the onset of symptoms, do not visit crowded places or seek consultation and examination. Get treatment at the nearest health facility as soon as possible.
Transmission: H5N1 bird flu is a flu virus that is usually transmitted from sick birds to other birds, but can sometimes be transmitted from birds to humans through close contact with sick or dead birds. Avian influenza in humans is a serious disease that requires timely hospitalization. Although it is not easily transmitted from person to person, if it can metabolize it can be as contagious as the seasonal flu.
Preventive measures: Government education messages include: Wash hands frequently with soap and water before eating and after contact with birds, keep children away from birds and keep birds away from living, do not eat birds. Sick or dead and all birds made for eating must be well cooked.
The Ministry of Health will continue to inform the public about information related to public health issues through the Telegram Channel and the official Facebook page of the Ministry of Health, as well as the official Facebook page of the Department of Infectious Diseases and the website www.cdcmoh.gov.kh, which has Health education materials that can be downloaded, viewed and used.For more information, please contact the Ministry of Health Hotline 115 for free.
Monday, March 3, 2067, Phnom Penh, February 12, 2024
Whenever a `cluster' of cases appears in a family, or a neighborhood, the question always arises whether it is a sign of human-to-human transmission.
When it comes to proving human-to-human (H-2-H) transmission of an emerging virus, the bar is intentionally set pretty high. When there are other, equally plausible explanations (e.g. shared environmental exposures), then H-2-H cannot be assumed.
Ten months ago, in UK Novel Flu Surveillance: Quantifying TTD, the HKHSA described some of the challenges in detecting or confirming community spread of H5N1 - even in the UK - until after dozens, or even hundreds, of cases had occurred.
In 2006, we saw several clusters of H5N1 infection in both Indonesia and Turkey, and yet, it never managed to gain enough momentum to spark a wider epidemic (see 2006 Karo Cluster Involved H2H Transmission).
A family cluster in Pakistan in 2007 raised similar concerns, but once again failed to catch fire (see EID Journal: Unraveling Pakistan’s H5N1 Outbreak).
Should we begin to see evidence of efficient and sustained H-2-H transmission (ie. 3rd, 4th, 5th generation transmission) - then things start to get considerably more concerning.